A Rat Must Press a Lever for a Variety of Food

question 38

Multiple Choice

A rat must press a lever for a variety of food options and access to water. When the schedule requirements for food options and water are varied, lever-pressing for food options varies as the schedule changes, but water consumption is not affected by the food schedule. In this scenario, water would be classified as a(n) _______ commodity.

• A) complement
• B) independent
• C) substitute
• D) alternative

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Definitions:

Venule

A small blood vessel that allows deoxygenated blood to return from the capillary beds to the larger blood vessels called veins.

Superficial Palmar Arch

An arterial network located in the palm of the hand, responsible for supplying blood to the fingers and hand.

Brachial Artery

A major blood vessel of the upper arm that supplies blood to the arm and hand.

Common Carotid Artery

A major artery in the neck that supplies blood to the head and neck, dividing into the internal and external carotid arteries.